Dr. Ronald Shaw, HER COLLEAGUE, concurs with the theory of a black hole at the galactic center of the milky way. The appositive phrase in this sentence is "her colleague" and this refers to the noun "Dr. Ronald Shaw". An appositive phrase consists of words that serves as an additional information about the noun it describes. Usually, appositive phrases are enclosed with a pair of commas.
Answer:
It is a pun.
Explanation:
This is because it is a figure of speech that exploits a word's meaning in this case that the book was impossible to put down.
